Boost termination valve

ABSTRACT

A boost termination valve for use in the oxidizer line of a hypergolic rocket motor comprising a flapper valve normally latched in open position to permit flow of oxidizer therethrough, and a pyrotechnic device for releasing the latch and urging the flapper toward its closed position to terminate the flow of oxidizer to the engine.

EJnited States Patent 11 1 1111 3,792,833 Rosin Feb. 19, 1974 BOOSTTERMINATION VALVE 3,006,596 10 1961 Nelson 2s1/22s x [75] Inventor:Alexander D. Rosin, Pontiac, Mich. O E G PATENTS OR APPLICATIONS [73]Assignee; The United States of America as 605,157 ll/l934 Germany l/228represented by the Secretary of the Army, Washington, DC PrimaryExaminer-Alan Cohan d: 14 1 72 Assistant Examiner-Richard Gerard [22]116 Aug 9 Attorney, Agent, or Firm-Edward J. Kelly; Herbert PP 8 ,285Berl; Herbert H. Murray [52] U.S. Cl 251/11, 25l/63.4, 251/228, 57ABSTRACT 251/297 51 1111. c1. Fl6k 1/20, Fl6k 31/163 A bow 'i valveX1d1zer 58 Field 61 Search 251/62 63.4, 76 228, 298, hypergohc Ocketcompnsmg a flapper 251/299 303 11 valve normally latched in openposition to permit flow of oxidizer therethrough, and a pyrotechnicdevice for [56] References Cited releasing the latch and urging theflapper toward its closed position to terminate the flow of oxidizer tothe UNITED STATES PATENTS engina 3,587,601 6/1971 Shippy 137/67 257,4495/1882 Pratt 251/303 X 4 Claims, 2 Drawing Figures 1 o I 2o 12 11a I lfi 6 so 90 a 4 v 84 92 a2 O 515 42 531 a f; h

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PAIENIE FEB I 91974 SHEET 1 0F 2 PAIENTED FEB l 9 i974 SHEET 2 OF 2 1BOOST TERMINATION VALVE BACKGROUND OF THE INVENTION In a rocket having ahypergolic boost engine it is desirable to terminate the boost when therocket reaches a predetermined velocity. Since the hypergolic fuelignites automatically when mixed with the oxidizer one method ofterminating the boost is to cut off the flow of either the fuel or theoxidizer.

It is therefore an object of this invention to provide a valve to cutoff the flow of oxidizer to a hypergolic engine.

Another object of the invention is to provide a cut off valve which isquick acting.

Another object is to provide a valve which is operated by firing apyrotechnic squib.

' BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partial longitudinalsection of the valve of the present invention showing the flapperlatched in its open positionv FIG. 2 is a similar section illustratingthe valve in closed position.

DETAILED DESCRIPTION OF THE INVENTION The valve of the present inventionhas a cylindrical housing 12 having an axial inlet port and a radialoutlet port 16. The housing 12 is adapted to slip into a recess in therocket engine (not shown) and be sealed by an O-ring 18 and positionedby an indexing pin 20.

A valve assembly generally indicated is formed by a body 31 positionedwithin the sleeve 12 by an indexing pin 32 and sealed by an O-ring 34.The end of the body 31 toward the inlet and outlet ports 14 and 16 isprovided with two forwardly extending ears one of which is illustratedat 36. A pin 38 is fixed within the ears 36.

A flapper assembly 40 faced with deformable material 41 and having arearwardly projecting leg 42 is mounted for pivotal movement on the pin38 which extends through a hole 44 provided in the leg 42. The hole 44is slightly elongated in a direction normal to the face 46 of theflapper 40 for reasons set forth herebelow.

The upper portion of the projection 42 is formed in the shape of a hookas illustrated at 48 having a forwardly facing surface 50.

The body 31 is bored as illustrated at 60 and a piston 62 is slideablymounted within the bore. The piston 62 is provided with a transverseslot 64 and a pin 66 extends through the slot to limit the travel of thepiston 62. An O-ring 68 provides a seal between the piston 62 and thewall of the bore 60.

The forward end 70 of the piston 62 is enlarged and slides within acounterbore 72 in the body 31. The enlarged end 70 of the piston 62 isprovided with an angular groove 74. A compressable snap lock ring 76 ismounted in the groove 74 and projects outwardly into an annulardepression 78 formed in the wall of the counterbore 72 to retain thepiston 62 in the position illustrated in FIG. 1.

A hook shaped projection 80 is fixed to the forward end of the piston 62and is provided with a rearwardly 6 facing surface 82 which engages thepreviously described surface 50 on the flapper 40 to latch the flapperin open position as illustratedin FIG. 1.

The rear of body 31 is bored and tapped as illustrated at 90 co-axialwith the bore 60. A pyrotechnic squib 92 is threaded into the opening90.

In the use of the valve of the present invention, the assembly 10 isinserted into an opening provided in the rocket motor (not shown). Theoxidizer for the motor flows through the valve entering through theinlet port and exiting through port 16. The valve is in the latched openposition illustrated in FIG. 1.

When the missile reaches the desired velocity the squib 92 is fired.Gases from the squib force the piston 62 to the left overcoming theresistance of the lock ring 76. When the piston 62 moves to the left thelatching face 82 on projection disengages from the latch face 50 on theprojecting portion 42 of the flapper 40. Continued movement of thepiston 62 causes the forward face of projection 80 to strike the rearface of projection 42 thus rotating the flapper 40 about the pivot pin38. When the flapper 40 rotates far enough for the fluid flow to strikethe back side of flapper 40, the flapper slams shut against the port 16closing said port to further flow. Prior to complete closure of flapper40 the motion of piston 62 is arrested by the action of the pin 66 inslot 64.

The deformable material 41 on the face 46 of flapper 40, together withthe looseness caused by the elongated hole44, insures complete closureof port 16.

I claim:

1. A valve mechanism comprising:

a housing having an inlet and an outlet,

a hinged flapper for closing the outlet of said housing,

latch means for releasably maintaining said flapper in open position, apiston and cylinder assembly, an actuator arm attached to the end ofsaid piston adjacent said flapper and positioned to release said latchmeans and close said flapper upon movement of said arm toward saidflapper, said piston having an elongated longitudinal slot therein, apin fixed to said housing and extending transversely through said slotto limit the motion of said piston to a position less than that requiredto completely close said flapper, and I means for driving said pistonand actuator arm toward said hinged flapper thereby rotating saidflapper toward a position closing said housing outlet. 2. A valvemechanism wherein:

said latch means comprises interengaging hook portions on said flapperand said actuator arm to maintain said flapper in open position untilsaid actuator arm moves toward said flapper.

3. A valve mechanism as set forth in claim 1,

wherein:

the hinge for said flapper comprises a pin fixed to said housing, anelongated hole in said flapper through which said pin extends, said holebeing elongated in a directionnormal to the face of said flapper topermit self centering action of said flapper when moved to closedposition. 4. A valve mechanism as set forth in claim 3 wherein: a layerof deformable material is mounted on the face of said flapper whichengages said outlet.

as set forth in claim 1,

1. A valve mechanism comprising: a housing having an inlet and anoutlet, a hinged flapper for closing the outlet of said housing, latchmeans for releasably maintaining said flapper in open position, a pistonand cylinder assembly, an actuator arm attached to the end of saidpiston adjacent said flapper and positioned to release said latch meansand close said flapper upon movement of said arm toward said flapper,said piston having an elongated longitudinal slot therein, a pin fixedto said housing and extending transversely through said slot to limitthe motion of said piston to a position less than that required tocompletely close said flapper, and means for driving said piston andactuator arm toward said hinged flapper thereby rotating said flappertoward a position closing said housing outlet.
 2. A valve mechanism asset forth in claim 1, wherein: said latch means comprises interengaginghook portions on said flapper and said actuator arm to maintain saidflapper in open position until said actuator arm moves toward saidflapper.
 3. A valve mechanism as set forth in claim 1, wherein: thehinge for said flapper comprises a pin fixed to said housing, anelongated hole in said flapper through which said pin extends, said holebeing elongated in a direction normal to the face of said flapper topermit self centering action of said flapper when moved to closedposition.
 4. A valve mechanism as set forth in claim 3 wherein: a layerof deformable material is mounted on the face of said flapper whichengages said outlet.